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A020306 Strong pseudoprimes to base 80. 1
9, 27, 49, 81, 169, 301, 481, 2107, 3439, 5461, 6253, 6401, 7107, 8261, 10349, 16609, 18361, 23281, 25351, 29089, 46531, 49051, 55231, 58969, 75851, 79501, 113401, 115231, 117569, 119341, 123139, 138881, 146611, 157753, 158701, 188501, 200911 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..300

Index entries for sequences related to pseudoprimes

MATHEMATICA

strongPseudoprimeQ[b_, n_] := Module[{rems = Table[PowerMod[b, (n - 1)/2^expo, n], {expo, 0, IntegerExponent[n - 1, 2]}]}, (rems[[-1]] == 1 || MemberQ[rems, n - 1]) && PowerMod[b, n - 1, n] == 1]; max = 5000; Select[Complement[Range[2, max], Prime[Range[PrimePi[max]]]], strongPseudoprimeQ[80, #] &] (* Alonso del Arte, Aug 10 2018 *)

CROSSREFS

Sequence in context: A062231 A133636 A020208 * A330680 A069068 A051412

Adjacent sequences:  A020303 A020304 A020305 * A020307 A020308 A020309

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified June 1 02:09 EDT 2020. Contains 334758 sequences. (Running on oeis4.)